The Prevalence of Stroke in Patients with Obstructive Sleep Apnoea

Background: Previous population and clinical studies have confirmed the relationship between stroke and obstructive sleep apnoea (OSA). Our previous study on the epidemiology of sleep-disordered breathing among the inhabitants of Warsaw, conducted on 676 subjects aged 56.6 ± 8.2 years in whom polysomnography was performed and OSA was confirmed in 76 cases (11.3%) with the mean apnoea-hypopnoea index (AHI) of 25.3 ± 16.1, revealed a low prevalence of stroke in subjects with OSA (2 subjects [2.6%]) and in subjects without OSA (20 subjects [3.4%]). The aim of the study was to evaluate the prevalence of stroke in newly diagnosed patients with OSA qualified for continuous positive airway pressure (CPAP) treatment. Material and methods: We investigated 342 patients (263 men and 79 women) aged 55.4 ± 10.1 years with severe disease (AHI 39.7 ± 22.5) and considerable obesity (body mass index [BMI] 35.0 ± 6.6 kg/m²). A history of stroke was confirmed in 16 patients prior to the initiation of CPAP (4.7%; Group 1). Group 2 (subjects without a history of stroke) comprised 326 subjects (95.3%). Results: Multiple regression analysis revealed a significant correlation between stroke and the time spent in desaturation below 90% at night (T90) during polysomnography (b = –0.22, p = 0.009), diabetes mellitus (b = 0.16, p = 0.006), Epworth sleepiness score (b = 0.14, p = 0.02), and coronary artery disease (b = 0.14, p = 0.03). Conclusions: A correlation was demonstrated between stoke in patients with OSA (before CPAP treatment) and overnight and daytime oxygenation, diabetes mellitus, daytime sleepiness, and coronary artery disease. The incidence of stroke in the study population was low (4.7%) and similar to that observed in previous population studies.